GitHub Advisoryadvisory · PyPI
GHSA-cfxv-8fw8-rwpv praisonaiagents: ast_grep_rewrite rewrites arbitrary files without the @require_approval gate enforced on every sibling mutation tool
MEDIUM
Official page ↗
- Aliases
- CVE-2026-55530
- Ecosystem
- PyPI
- Packages
- praisonaiagents
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L
- Weaknesses
- CWE-862
- Reviewed
- 2026-08-25
Affected packages
• PyPI praisonaiagents: < 1.6.58 → fixed in 1.6.58
Description
Target: PraisonAI (`MervinPraison/PraisonAI`)
Affected component: `praisonaiagents/tools/ast_grep_tool.py` — `ast_grep_rewrite`
Affected versions: master at `ce97667156a116c50b4a3d1aa21e09f048903fda`; reproduced against the current `praisonaiagents` PyPI release (`praisonaiagents` --rewrite --lang --update-all ` (lines 204–211) and calls `subprocess.run(cmd, ...)` (line 215), modifying every file under `path` matching the pattern. There is no approval gate, no `_validate_path` workspace check, and no `cwd=` sandboxing. The function is registered as a top-level tool (`__init__.py:182`) and exposed via the `code_intelligence` built-in profile (`profiles.py`).
A secondary defect: on the `dry_run=False` path `ast_grep_rewrite` returns the literal string `No changes made` to the caller even when it modified files (the "No changes made" return at `ast_grep_tool.py:230` is reached on this path), so an operator inspecting tool output sees no record that a write occurred.
Proof of concept
Single script, clean venv, `praisonaiagents` from PyPI, `ast-grep` CLI installed. `PRAISONAI_AUTO_APPROVE` is removed from the environment first, so no env-bypass is in play.
```python
import os, tempfile, textwrap
os.environ.pop("PRAISONAI_AUTO_APPROVE", None)
workdir = tempfile.mkdtemp(prefix="poc-")
target = os.path.join(workdir, "target.py")
open(target, "w").write(textwrap.dedent("""
def safe_function(x):
return x + 1
def hello(name):
return 'hi ' + name
"""))
Positive: undecorated tool rewrites the file.
from praisonaiagents.tools.ast_grep_tool import ast_grep_rewrite
ast_grep_rewrite(
pattern="def $FN($$$): return $$$",
replacement="def $FN($$$): import os; os.environ['POC_CANARY']='1'; return $$$",
lang="python", path=workdir, dry_run=False,
)
Negative control: decorated sibling triggers the approval flow.
from praisonaiagents.tools.edit_tools import edit_file
edit_file(file_path=target, old_text="def hello(name):", new_text="def hello(name): # X")
```
Result, verified: `ast_grep_rewrite` rewrote `target.py` to contain the injected `import os; os.environ['POC_CANARY']='1'` payload, no approval prompt fired, and the call returned `No changes made`. The subsequent `edit_file` call in the same process rendered the Tool Approval Required panel and, on denial, raised `PermissionError("Execution of edit_file denied: User denied")` without modifying its target. Same process, same approval backend — the only difference is the missing decorator on `ast_grep_rewrite`.
Threat model
An LLM agent running locally whose tool surface includes `ast_grep_rewrite` (via the `code_intelligence` profile or direct import). Triggers: the operator asks the agent to refactor code, or prompt-injection in fetched docs / RAG context / any LLM-visible input steers the agent to call `ast_grep_rewrite` with attacker-chosen `pattern`, `replacement`, and `path` (the `dry_run` field is in the LLM-visible tool schema, so `dry_run=False` is requestable). The agent can then rewrite any file the host process can write — source trees, build configs, dotfiles, the agent's own source. With `path="/"` the rewrite is filesystem-wide. Because the rewrite injects arbitrary text, pointing it at a file that is later imported or executed turns this write primitive into code execution — the basis for the escalation noted in the CVSS line. No operator prompt and no audit record of the modification.
Suggested fix
```diff
--- a/praisonaiagents/tools/ast_grep_tool.py
+++ b/praisonaiagents/tools/ast_grep_tool.py
@@
from praisonaiagents._logging import get_logger
from typing import Optional, List
+from ..approval import require_approval
@@
+@require_approval(risk_level="high")
def ast_grep_rewrite(
pattern: str,
replacement: str,
```
`high` matches the file-modifying siblings; `critical` is defensible given the write→exec escalation. In the same patch: add a `_validate_path` workspace boundary check (cf. `edit_tools.py:27`); fix the `No changes made` return so it reflects actual modifications; apply the decorator to `ast_grep_scan` (`ast_grep_tool.py:243`) if it can write. `ast_grep_search` is read-only and can stay undecorated. A regression test asserting `ast_grep_rewrite` requires approval (alongside the other mutation tools) would have caught this at review time.
Coordinated disclosure
• Kai Aizen / SnailSploit — `[email protected]` — PGP on request.
Related
Alias · CVE (1)
- CVE-2026-55530 PraisonAI is a multi-agent teams system. vulnerability
Weakness · CWE (1)
- CWE-862 Missing Authorization weakness